Mycophenolic acid (MPA) is a natural compound produced by some fungi, mainly of the Pencicillum fungus species. MPA has a wealth of applications; the most important application at present being a key drug in the treatment of organ transplanted patients. MPA was first discovered in 1893 and has been investigated thoroughly since its discovery. However, despite the importance of this drug, no information is available about the enzymes responsible for MPA synthesis in the fungus. On an industrial scale, MPA is thus currently produced by relatively laborious and inefficient fermentation processes of the natural fungus, primarily Penicillium brevicompactum. 
Hence, there exists a need in the art for improved methods for producing MPA. Furthermore, it is likely that new commercial applications of MPA, and thereby an increased demand for the compound, will result from cheaper and more efficient production methods.